Various lamps with adjustable reflectors are known, in which rigid parts of the reflectors are supported so that they can pivot around their longitudinal axis with respect to the fluorescent tube. As a result, it is possible to deflect the beam characteristic of the reflector part in question as a whole in different directions, that is, upward, to the side, or downward. With the known devices, however, it is not possible with the known reflector to vary the beam characteristic over a wide range, such as between a wide-beam and a narrow-beam characteristic, or to give it an asymmetric characteristic.